The goal of this research is to test the efficacy of a collagen meniscus template to promote host meniscal fibrocartilage regeneration. The template is non-toxic and biodegradable and is fabricated from natural connective tissue components. In earlier studies, the potential of this template to support meniscal cartilage regeneration was shown. Phase I will evaluate the degradation rate of an improved version of the template in rabbit stifles and test the template in a dog model. Phase II will concentrate on larger numbers of animals for statistical analysis of a direct comparison between the collagen meniscus template and conventional meniscal resection. Specific Aim 1 will focus on the optimization, production, and quality control testing of the improved collagen meniscus template. Specific Aim II will measure the template's degradation rate in the rabbit stifle. Specific Aim III will evaluate the performance of the template in the canine stifle. Using anatomic, biochemical and physico-chemical techniques, we will quantify and directly compare current standard meniscal resection alone to the new collagen meniscus template. Potential commercial application of an effective meniscal fibrocartilage template can be appreciated from U.S. Bureau of Health Statistics (1986) estimates that currently more than 1.4 million operations related to meniscus injuries and degenerative arthritis are performed in the United States. Accumulated experimental and clinical data have demonstrated that the abnormal force distribution on the tibial plateau post meniscectomy has led to early degenerative arthritis. No accepted treatment except excision for the irreparably damaged meniscus exists necessitating technological innovation in the practice of clinical orthopaedics for meniscus repair.